1/2" x 3-1/2" Zinc Plated Steel Wej-It Anchors WAS-336 (50 pcs.)Type: Anchor Bolts
Drill Size: 1/2"
Type: Wedge Anchor
Box of 50.
All mechanical bolts have a wedge arrangement at the end. Tightening the bolt results in a wedge being driven up against a sleeve. This jams the end of the bolt, and provides the strength.